人造沸石的载铁改性及除去水中氟的性能

Removing Fluoride from Water Using Permutite Modified with Ferric Chloride

以人造沸石为载体,采用盐酸浸泡活化和氯化铁溶液浸泡改性的方法制备除氟吸附剂,用模拟高氟水样进行静态吸附及动态过柱实验。动力学研究结果表明：吸附剂吸附速度快,40 min接近吸附平衡,吸附速率可用拟二级动力学方程描述。吸附等温线符合Langmuir方程,饱和吸附量为9.83 mg/g,吸附平衡常数为0.030 2 L/mg。静态实验对浓度为10.43 mg/L的含氟水样投加7.0 g/L吸附剂,除氟率达91.56%。动态实验有效除氟容量（指出水的氟离子含量低于1.0 mg/L的除氟容量）达2.78 mg/g。除氟后沸石可采用0.1 mol/L NaOH溶液洗脱,100 g/L的氯化铁溶液再生,再生效率达113%。溶液pH值对除氟有较大影响,除氟最佳在pH 5~6。共存CaCl2对静态和动态除氟的影响不同,增大CaCl2浓度有利于静态除氟,不利于动态除氟。温度对吸附有一定影响,升高温度不利于吸附。

This paper involves preparation of ferric-modified permutite in lab scale,as well as static and dynamic adsorption column tests in order to study removal of fluoride from water.The dynamic adsorption study reveals that the equilibrium adsorption data fit well to Langmuir adsorption isotherm with equilibrium constant of 0.030 2 L/mg,and the max adsorption capacity is 9.83 mg/g.Regeneration of the modified permutite that has been fluoride-saturated is made possible by elution with sodium hydroxide followed by soaking with ferric chloride solution of 100 g/L.Other parameters that are presumed to affect fluoride adsorption are investigated as well,such as pH,temperature and co-existed calcium chloride in the water.